INSERT()() — SQL Technical Interview Questions & Answers

INSERT()()

INSERT()()

  • INSERT() is a MySQL string function — it takes text and returns text or a number. You use it in SELECT (and sometimes WHERE/UPDATE). It does not change stored data unless you UPDATE … SET col = INSERT(col).
  • Board: SELECT INSERT(name) FROM students; Run it. Say the result out loud. If the column is NULL, the result is often NULL — wrap with IFNULL if you need a blank instead.
  • String indexes in MySQL start at 1, not 0 (SUBSTR, INSTR, LEFT). NULL input often yields NULL. Try it on one row first.
  • Interview: name INSERT, one argument list, one example on the students table. Don’t recite every string function.
  • On the example next to this theory: INSERT()() — iNSERT adds rows. List columns explicitly for clarity.

Technical Interview Tip: Say what INSERT returns, then SELECT INSERT(name) FROM students;

Code Examples for INSERT()()

INSERT()() — sample query

CREATE TABLE products (id INTEGER PRIMARY KEY, name TEXT, price REAL);
INSERT INTO products (id, name, price) VALUES
  (1, 'Mouse', 499),
  (2, 'Keyboard', 999);
SELECT * FROM products;

INSERT()() — iNSERT adds rows. List columns explicitly for clarity.

How to Explain INSERT()() to an Interviewer

What does INSERT do?

is a MySQL string function — it takes text and returns text or a number SELECT INSERT(name) FROM students;

Does it UPDATE the table?

No, unless you write UPDATE SELECT only prints